I spy with my little eye something that moves vividly: The role of mental imagery in animacy perception based on motion cues

Abstract

Animacy perception describes the ability to distinguish between animate and inanimate entities. Since motion cues are common indicators of animacy, moving inanimate objects can also appear animate. We investigate the role of visual imagery in animacy perception, hypothesizing that movements of inanimate objects lead to a stronger attribution of animacy when people are able to visualize. 133 participants with various mental imagery abilities, including 42 aphantasics, were presented with a dot moving on a computer screen and instructed to imagine that they were looking through a window at an object moving outside. The dot mimicked the movements of a fly exploring a room (most animate-looking stimulus), the movements of a leaf blown around by the wind (most inanimate-looking stimulus), or one of four intermediary stimuli, all generated by a mathematical parametric movement equation. Participants had to decide whether the object represented by the dot was animate or inanimate. For more animate-looking stimuli, participants with higher vividness of mental imagery were faster to distinguish between animate and inanimate entities. By fitting a drift-diffusion model to the response time data, we estimated drift rates and decision biases. These parameters suggest that aphantasics did not use slower decision strategies, but were more strongly biased towards inanimate decisions.